As applications evolve over time, it becomes increasingly desirable to be able to adapt a system, enabling it to handle situations in different ways and to handle new situations. We refer to this as the flexibility and maintainability of a system. These features come at a cost. We argue here that they are an important aspect of evaluation, and that we need to measure these costs. To start getting a handle on how one might evaluate these aspects of a system (or of an approach), we turned to our own approach to building AH applications and designed a specific study to allow us to look at these issues.